Git 更改已提交的操作

git reflog 查看当前仓库的所有操作日志

$ git reflog
d16f2f4 HEAD@{7}: commit (amend): Merge branch "fix-B"
b110cfe HEAD@{8}: commit (merge): Fix conflict
d8b19ab HEAD@{9}: checkout: moving from fix-B to master
8340da0 HEAD@{10}: checkout: moving from master to fix-B
d8b19ab HEAD@{11}: checkout: moving from feature-A to master
04f1afd HEAD@{12}: checkout: moving from fix-B to feature-A
8340da0 HEAD@{13}: reset: moving to 8340da0
d8b19ab HEAD@{14}: checkout: moving from master to fix-B
d8b19ab HEAD@{15}: reset: moving to d8b19ab
9ba9239 HEAD@{16}: checkout: moving from fix-B to master
d8b19ab HEAD@{17}: reset: moving to d8b19ab
8340da0 HEAD@{18}: commit: Fix B
9ba9239 HEAD@{19}: checkout: moving from fix_b to fix-B
9ba9239 HEAD@{20}: checkout: moving from master to fix_b
9ba9239 HEAD@{21}: reset: moving to 9ba9239561b2ba36c7b2be2c2378aecc09ca8db8
d8b19ab HEAD@{22}: merge feature-A: Merge made by the 'recursive' strategy.
9ba9239 HEAD@{23}: checkout: moving from feature-A to master
04f1afd HEAD@{24}: checkout: moving from master to feature-A
9ba9239 HEAD@{25}: checkout: moving from feature-A to master
04f1afd HEAD@{26}: commit: Add feature-A
9ba9239 HEAD@{27}: checkout: moving from master to feature-A
9ba9239 HEAD@{28}: commit: Add index
b1c8e4f HEAD@{29}: commit: commit README file
6e5f9c7 HEAD@{30}: commit (initial): First commit

• reflog git log 命令只能查看以当前状态为终点的历史日志，使用 git reflog 可以查看所有的历史操作日志。

---

git reset 回溯历史版本

$ git reset --hard 8340da0
HEAD is now at 8340da0 Fix B

• --hard 要让仓库的HEAD、暂存区、当前工作树回溯到指定状态，需要通过 git reset --hard 命令进行操作。

---

消除冲突

• 在分支合并的过程中，会出现文件冲突的情况，这个时候需要我们手动消除冲突：

$ git merge --no-ff fix-B
Auto-merging README.md
CONFLICT (content): Merge conflict in README.md
Automatic merge failed; fix conflicts and then commit the result.

• 打开冲突的文件进行查看：

$ vim README.md 
# Git 教程
<<<<<<< HEAD
-feature-A
=======
-fix-B
>>>>>>> fix-B

• ======= 以上的部分是当前HEAD的内容，以下的部分是需要合并的内容，我们手工将其修复：

# Git 教程
-feature-A
-fix-B

• 修复了冲突后，提交文件即可：

$ git add README.md 
$ git commit -m "fix conflict"
[master c03e2d7] fix conflict

---

git commit --amend 修改上一条提交的信息

• 当我们提交的信息有误，需要修改的时候，可以使用 git commit --amend 命令：

$ git commit --amend

编辑器会打开并显示上一条修改信息：

fix conflict
# Please enter the commit message for your changes. Lines starting
# with '#' will be ignored, and an empty message aborts the commit.
#
# Date:      Tue May 16 16:26:47 2017 +0800
#
# On branch master
# Changes to be committed:
#       modified:   README.md

• 修改了并保存编译器中的内容，即可完成修改：

[master dfa52fb] Merge branch 'fix-B'
 Date: Tue May 16 16:26:47 2017 +0800

• 执行 git log --graph，可以看到历史中的对应记录也被修改为最新的内容：

$ git log --graph
\*   commit dfa52fbc655efe39c94fe8a9cda814ee8cc4d054
|\  Merge: 96d8c7b 046d2e2
| | Author: JannyHo <fung.w.chan@hotmail.com>
| | Date:   Tue May 16 16:26:47 2017 +0800
| | 
| |     Merge branch 'fix-B'
| |   
| * commit 046d2e2f63c86b3431dc3cc28775d567f583c447
| | Author: JannyHo <fung.w.chan@hotmail.com>
| | Date:   Tue May 16 16:16:00 2017 +0800
| | 
| |     fix-B
| |     
\* |   commit 96d8c7bca7dbbdfa012f4977696f76994d1c3d59
|\ \  Merge: 2561af2 186162c
| |/  Author: JannyHo <fung.w.chan@hotmail.com>
|/|   Date:   Tue May 16 16:16:27 2017 +0800
| |   
| |       Merge branch 'feature-A'
| |   
| * commit 186162c5fef8eff5a2c79d3f7d5bb4155a4d72e1
|/  Author: JannyHo <fung.w.chan@hotmail.com>
|   Date:   Tue May 16 16:11:14 2017 +0800
|   
|       feature-A
|  
\* commit 2561af291bb9b1065c5bb15122cc0739fbb4d8e8
  Author: JannyHo <fung.w.chan@hotmail.com>
  Date:   Tue May 16 16:09:58 2017 +0800
      First commit

---

git rebase -i 压缩历史

• 在合并特性分支前，如果发现已提交的内容在有错误，可以提交一个修改，然后将这个修改合并到前一个提交中压缩成一个历史记录：

我们先创建一个新的特性分支 feature-C：

$ git checkout -b feature-C
Switched to a new branch 'feature-C'

我们在 feature-C 中修改了 README.md，在此处有一个拼写错误：

> # Git 教程
> 
> - feature-A
> - fix-B
> - faeture-C

我们先提交这些修改(git add 和 git commit -m 可以简写为 git commit -am)：

$ git commit -am "Add feature-C"
[feature-C e015d1c] Add feature-C
 1 file changed, 1 insertion(+)

我们把 README.md 中的 faeture-C 改为拼写正确的 feature-C，并查看一下修改的内容：

> $ git diff
> diff --git a/README.md b/README.md
> index 4d32145..1c9d4ee 100644
> --- a/README.md
> +++ b/README.md
> @@ -2,4 +2,4 @@
> 
> - feature-A
> - fix-B
> -- faeture-C
> +- feature-C

我们提交这些修改：

$ git commit -am "Fix typo"
[feature-C dd18150] Fix typo
 1 file changed, 1 insertion(+), 1 deletion(-)

这种小修改在历史记录中没有意义，所以我们要想办法把它去掉：

未完待续